Intellectually engaged…intensely humane… exuberantly speculative was Iain M Banks' blurb for 2312. So who am I to disagree with one of the current masters of the genre?

No-one. Just an ordinary reader. And actually, the more I think about the less I do – actually – as such – disagree. Banks' phrases are true and accurate. They're just not the whole story. Not for me anyway.

For a reader, as opposed to another writer, the book is much more difficult than that. Publishers Weekly called it challenging and that's much nearer the mark.

2312 we are given to understand is / will be / was a pivotal year. It is the year in which most of the action of the book takes place, but obviously it's way in our future, and parts of the book look back on it from some undetermined distance beyond. How and why it proves to be pivotal is one of the unanswered challenges. Make of it what you will.

The problem with the book is that it is something more than A book, or tries to be, and so for me ends up being something less than one. Oh, it's clever and challenging and exuberant and all of that… but it falls over its own cleverness and ends up being annoying and irritating for not having been 'settled' into one place or the other.

Let me explain.

Book 1: There is a story to be told. The story of Swan and Wahram. We can think of these characters as she and he – although by this time genders have become so mixed and blurred that they are merely self-assigned predominant preferences, usually in varying combinations of masculine/feminine, reinforced by surgery, chemical intervention and lifestyle. The story of Swan and Wahram starts with the death of Swan's grandmother (Alex) a high-powered Mercurian involved in all sorts of interplanetary intrigue, a much-respected leader and diplomat.

Swan herself is an artist: largely a landscape artist of both the Goldsworthy mould and in some senses of the Capability Brown one too in her early years terraforming inside asteroids.

Warham is from Titan prognathous, callipygous, steatopygous, exophthamlus , or as Swan then thinks it toad, newt, frog. I'm not sure I ever fully grasped what his profession is: some kind of trade envoy seems near the mark, but he was one of Alex's confidantes.

Not exactly a match made in heaven. As the events turn it becomes clear that it might become a match made in hell: the hell that follows an attack on Swan's home city. A city on Mercury is one of the wildly speculative scientific extrapolations that will have hard-core sci fi fans loving this book, but we'll come back to that.

Swan and Warham get caught up in intergalactic politics, terrorism and intrigue and in true thriller fashion chase after the bad guys, fall in love, fall out, get hurt and face death. Not necessarily in that order and not necessarily only the once. Of course this being Sci-fi, there is also the threat that quantum computers (Qubes) without whose AI, none of the modern conveniences can function, may just be evolving into androids with genuine consciousness and a kind of free will.

The Swan and Warham tale (which I choose to think of as 'book 1') is the heart and momentum of the book. It's the bit that will eventually make the screen play. 'Book 1' is entirely my invention and bears no resemblance at all to Robison's structure.

'Book 2' (in my head) is something of a poetry anthology. This is made up of chapters that intersperse the narrative. Chapters called Lists. They are what they say they are. Simple - or maybe not so simple - lists. Some of them hit the mark as pure poetry. Others count at least as lyrical prose. What their purpose is intended to be and whether they meet it comes under that heading challenging. Some of them I loved, some of them I got so bored with I skipped over them. Which might be another way of saying some work, some don't. The book would have been none the poorer without them. As an anthology, they could probably stand alone. For those who like their literary allusions, the echoes for me were of Vonnegut and Jim Morrison… which is both compliment and condemnation.

'Book 3' is the back-story, the history book. Extracts again litter the pages between the story and the Lists. These are the half-formed explanations of how things got to where they got to. Presented as extracts from history books which post-date the story by who-knows-how-long they explain how earthlings have managed to colonise the solar system, building homes on (or in) all of these uninhabitable planets. They explain the politics that resulted. They describe how you terraform the inside of an asteroid and what it's like to be within one. They explain how you can speed up a planet's spin to give it a usable day-length or how you build a city that needs to stay of the dark side of rotating planet. All of this is the author showing that he has thought his universe through, that given particular scientific extrapolations it isn't impossible. And that's my problem with it. All of these chapters read like some kind of proof, a self-justification for a world that either doesn't need one, or that needs one that he couldn't find a proper way of building into the story line. This for me is the book's real failure.

The very nature of these chapters is that they are presented as extracts i.e. disconnected paragraphs. They read like the construction notes for the novel. To me it felt as though a novel had been padded out with all of the research and theory and speculation that went into its making, lifted straight from the work in progress notebook. It felt both imposing and lazy. It's a purely personal view, but I strongly feel that if the reader NEEDS to understand then you have to show it through the story, and if we DON'T then you can leave it out entirely.

To me it felt that like the author saying: look how clever I am. And I responded, as a reader, with no, you're not, you're interrupting your own story, which is the bit I'm really interested in.

There are also a couple of Quantum Walks which are amalgams of the narrative, the Lists, the extracts… and more confusing than any of them.

So what do I make of the whole? Hard work, would be the unfortunate answer, and it is a shame on many levels. The backbone story: the actual narrative, I loved. When it was allowed to continue for any length of time without interruption I got caught up in it and began to care about our main protagonists, but too often I had to be pulled back out of that, like it was justification enough for a novel.

The scientific speculation is brilliant. I don't dispute that at all. It leaves you wondering if, just, maybe, could it… ????? And that has to be part of the point of Sci-Fi writing. Unfortunately, it is just too much in-your-face, laid-bare, this-is-why-you-have-to-accept-my-premise, rammed down your throat. I'd rather the really important bits had been worked into the story line and the rest just ditched - or sent to one of the relevant magazines as justification for the book, so that the real geeks can read it and the rest of us can take it on trust.

The Lists, like I say, were hit and miss. I could have lived with them if they were the only interruptions.

The Quantum Walks, especially the second one, come across as lazy plot devices to move the action on without bothering to write it out. Didn't like them at all.

So: as a book – for me a mixed bag that was hard work that didn't reward adequately, but I think I'm going to adore the film; for genuinely geeky Sci-Fi folks, I think they'll like it a lot. On which basis I have to star it between a three and five and come up with four.